The risk of extreme heat events and the adverse impacts on older people has been extensively discussed in research. Remarkably, very little attention has been paid to the role of urban greenery in reducing heat stress for seniors.

Older people are particularly at risk of heat stress. Pre-existing medical conditions and limited mobility increase their vulnerability. Deaths of older people increase during extreme heat events.

The physical features of urban areas shape the capacity of older adults to engage in many activities when it’s hot. These include vegetation volume and coverage, thermal design, and the extent of shading in public areas and walkways. Increasing urban greenery may offer a way to improve older people’s comfort and social experience.

Ageing adds urgency to greening

It is expected 20% of the global population will be older than 60 by 2050. The figure for Australia is even higher, at 23%. This means that by 2050 around one in four Australians will be more vulnerable to extreme heat.

Planning our urban centres to meet the needs of a rapidly ageing population is a matter of urgency. Urban greening to reduce their vulnerability to heat stress should be central to this agenda. It can also improve people’s quality of life, reduce social isolation and loneliness, and ease the burden on health systems.

An important task is matching the design of communities with the needs of an ageing population. Where older adults live and the quality of their local areas strongly influence their lived experiences. Yet recent research found the experiences of seniors were often not accounted for in research on neighbourhood design.

If one in ten Australian seniors live in aged-care facilities, it is clear these should be designed to minimise heat stress. This isn’t just good for residents; it may also benefit operators by lowering health-care and electricity costs.

While these facilities are purpose-built for older people, many in Australia were built well over a decade ago, when heat stress was not such a large concern. Many more facilities are being built now and will be into the future. Yet it is uncertain whether they are being actively designed to reduce the impacts of heat.

What has our research found?

We recently conducted a focus group to investigate this issue. Participants were senior managers from four large corporate providers of aged care in Australia. We investigated if and how providers try to minimise heat stress through design. We also sought to understand the rationales used to support these design approaches.

Several participants reported on refurbishments that they expect will have cooling effects. Cited design approaches included green roofs and walls, as well as sensory gardens. Other expected benefits included reducing anxiety and improving the mental health of residents.

The fact that single design interventions could produce multiple benefits improved the potential for corporate buy-in. Participants expected that increasing green space and green cover would give their facilities a competitive advantage by attracting more clients and providing a better working environment for staff.

Participants also reported on challenges of including greening in their projects. For example, the benefits of trees were weighed against concerns about roots disrupting footpaths and becoming trip hazards. Species selection was another concern, with fears that inappropriate plants could die and undermine support for greening programs.

Our research suggests that more can be done to make cities hospitable for older people, especially during extreme heat. Urban greening is a start. Encouraging aged-care providers to adopt green infrastructure will have benefits. But we should also consider reforms to planning systems and urban design to better protect older people who choose to age in place.

Extreme heat affects the mental health of Australians to the same degree as unemployment, yet Australia’s policy action on climate change lags behind other high-income countries such as Germany and the United Kingdom.

As Australia approaches another summer, we face the inevitability of deadly heatwaves. Our report published today in the Medical Journal of Australia concludes that policy inaction, particularly at the federal level, is putting Australian lives at risk.

Australia is the first to prepare its own country-level report. Developed in partnership with the Lancet Countdown – which tracks the global connections between health and climate change – it adopts the structure and methods of the global assessment but with an Australian focus.

How Australians’ health suffers

Australians are already facing climate change-related exposures that come from increasing annual average temperatures, heatwaves and weather-related disasters. Australian deaths during the 2014 Adelaide heatwave and Melbourne’s 2016 thunderstorm asthma event are examples of the risk climate poses to our health.

Our report was produced by a team of 19 experts from 13 universities and research institutes. We aimed to answer what we know about climate change and human health in Australia and how we are responding to this threat, if at all.

To do this, our team examined more than 40 indicators that enable us to track progress on the broad and complex climate change and human health issue. Health impact indicators included the health effects of temperature change and heatwaves, change in labour capacity, trends in climate-sensitive diseases, lethality of weather-related disasters and food insecurity and malnutrition.

We also developed an indicator for the impacts of climate change on mental health. This involved examining the association between mean annual maximum temperatures and suicide rates for all states and territories over the last ten years.

We found that, in most jurisdictions, the suicide rate increased with increasing maximum temperature. In Australia’s changing climate, we urgently need to seek ways to break the link between extreme temperature and suicide.

Across other indicators, we found workers’ compensation claims in Adelaide increased by 6.2% during heatwaves, mainly among outdoor male workers and tradespeople over 55 years.

And we found the length of heatwaves increased in 2016 and 2017 in Australia’s three largest cities – Sydney, Melbourne and Brisbane. Heatwave length varied from year to year, but between 2000 and 2017, the mean number of heatwave days increased by more than two days across the country.

Policy action we need

Australia’s slow transition to renewables and low-carbon electricity generation is problematic, and not only from a climate change perspective. Our report shows that pollutants from fossil fuel combustion cause thousands of premature deaths nationwide every year. We argue even one premature death is one too many when there is so much that we can do to address this.

Australia is one of the world’s wealthiest countries with the resources and technical expertise to act on climate change and health. Yet Australia’s carbon intensity is the highest among the countries we included in our comparison – Germany, United States, China, India and Brazil.

A carbon-intensive energy system is one of the main drivers behind climate change. Australia was once a leader in the uptake of renewables but other nations have since streaked ahead and are reaping the benefits for their economies, energy security and health.

Policy leaders must take steps to protect human health and lives. These include strong political and financial commitments to accelerate transition to renewables and low-carbon electricity generation. The government lacks detailed planning for a clean future with a secure energy supply.

Our MJA-Lancet Countdown report will be updated annually. Now that Australia has begun systematically tracking the effects of climate change on health – and given its poor performance compared with comparable economies globally – further inaction would be reckless.

On Wangkumarra land, in the corner-country near the borders of Queensland, New South Wales and South Australia, stands an ancient stone arrangement. It has been placed to the side of a huge complex, rivalling Stonehenge, featuring megaliths polished, carved and placed to balance precariously on each other.

Ancient stone arrangements on Wangkumarra land.Tyson Yunkaporta

They should fall, but they don’t, as this is a place where time runs differently. In contrast to the Western “arrow of time”, the small rock formation pictured shows the non-linear, infinitely interconnected cycle of time followed by the First People who built the site and used it over millennia. It is a stone calendar, aligned within a fraction of a millimetre to the points of the compass.

The stone calendar on Wangkumarra land.Tyson Yunkaporta

The key to understanding this temporal reality is the shape of the stone calendar. It is round, not a continuum. There is no beginning or end, and as such, there is no “New Year”. Seasons do not serve as a basis for linear metaphors of new life in spring to death in winter.

Instead, both seasons and humans are viewed as components of cycles. Around Australia, Indigenous languages vary in both the number of season words in their lexicon and their precise meaning. This is at least partly due to the very different kinds of weather experienced around the year in different parts of the country.

A tour of the seasons

In the Tiwi islands just to the north of Darwin there are three major seasons named in the Tiwi language: Kumunupunari (the dry season of fire and smoke); Tiyari (the season of hot, humid weather); and Jamutakari (the wet season of daily rain and full rivers). These three seasons subsume 13 overlapping, more precisely defined seasons.

For example, in the Mumpikari season (which overlaps with the start of the Jamutakari “wet season”) the first rains after the dry time make the ground soft and muddy enough to retain the footprints left by possums returning to their trees, which makes the possums easier to track when hunting.

Understanding the meaning of a word like Mumpikari “season of muddy possum tracks” entails knowledge of the type of weather experienced at that time (first rains following a long dry spell), consequent changes in the local ecology (muddy ground), as well as changes in human behaviour and potential sources of food (it’s a good time to hunt and eat possums).

The changes in weather, ecology and potential food sources over the course of the year are dramatic, but vary significantly across a continent as large as Australia. The season experienced in tropical Cape York in January is very different to January in Tasmania. Likewise, the middle of the year brings radically different weather patterns to the tropical north, temperate south and central desert regions respectively.

The definitions of seasonal terms tell us a lot about the ecology that a language is spoken within and how speakers interact with it. In the Warlpiri language of the Tanami Desert, for example, several seasonal terms (such as karapurda) make reference to the prominent westerly winds that blow at the onset of the hot season.

Common food sources also feature prominently in the definitions of season terms, such as mangkajingi, “season of year when goannas are easily found in shallow burrows”. In the Bardi language of the Dampier Peninsula (WA), the build up to the wet season is named Lalin and colloquially referred to as “married turtle season”, because the mating turtles are a prized food source at this time.

In Gulumoerrgin (Larrakia) language group, spoken around Darwin, the year is divided into seven named seasons. Each of these seasons is associated with distinctive patterns of weather, but also changes in flora, fauna, and human activity. The Gurrulwa season, or “big wind time”, is heralded by the flowering of wattles, which in turn indicates that the local stingrays are plentiful and good to eat. The flowering of the Yellow Kapok at this time in turn indicates that it is the time for important traditional ceremonies to be held.

Connections

These connections between species are often cemented in language by using a single word. In the Dalabon language of Arnhem land, the word yawok has two meanings: (1) a species of yam (Dioscorea bulbifera); and (2) a species of grasshopper (Caedicia spp.). To the untrained observer, the yam and grasshopper might appear to have little in common.

But for Dalabon speakers, this naming practice is a useful mnemonic that helps them remember that the yam is ripe for harvest precisely at that time of year when the grasshopper’s mating call can be heard. Similar principles have been found to underpin the naming of plant and animal species in languages such as Bininj Gun-Wok and Ndjébbana.

The words of any language tell us a lot about the history of its speakers; who they’ve been in contact with, where and how they have lived. This is certainly true of the English calendar months. It is also seen in the number and nature of the seasons named by different Indigenous communities, from the tropical north of Australia to the chillier climates down south.

With around 370 languages and many hundreds more dialects originally spoken in Australia, it is impossible to do justice to the wealth and variety of traditional systems of tracking time and seasons. But a recurrent theme is the interconnectedness of human activities and the cycle of changes in flora and fauna that attend the tilting of the earth’s axis.

A sustainable Australia is possible – but we have to choose it. That’s the finding of a paper published today in Nature.

The paper is the result of a larger project to deliver the first Australian National Outlook report, more than two years in the making, which CSIRO is also releasing today.

As part of this analysis we looked at whether achieving sustainability will require a shift in our values, such as rejecting consumerism. We also looked at the contributions of choices made by individuals (such as consuming less water or energy) and of choices made collectively by society (such as policies to reduce greenhouse gas emissions).

We found that collective policy choices are crucial, and that Australia could make great progress to sustainability without any changes in social values.

Competing views

Few topics generate more heat, and less light, than debates over economic growth and sustainability.

At one end of the spectrum, “technological optimists” suggest that the marvellous invisible hand will take care of everything, with market-driven improvements in technology automatically protecting essential natural resources while also improving living standards.

Unfortunately, there is no real evidence to back this, particularly in protecting unpriced natural resources such as ocean fisheries, or the services provided by a stable climate. Instead the evidence suggests we are already crossing important planetary boundaries.

Other the other end of the spectrum, people argue that achieving sustainability will require a rejection of economic growth, or a shift in values away from consumerism and towards a more ecologically attuned lifestyles. We refer to this group as advocating “communitarian limits”.

A third “institutional reform” approach argues that policy reform can reconcile economic and ecological goals – and is attacked from one side as anti-business alarmism, and from the other as indulging in pro-growth greenwash.

Income up, environmental pressures down

My colleagues and I have spent much of the past two years developing a new framework to explore how Australia can decouple economic growth from multiple environmental pressures – including greenhouse emissions, water stress, and the loss of native habitat.

We use nine linked models to assess interactions between energy, water and food (and links to ecosystem services) in the context of climate change.

The National Outlook focuses on the intersection of water, energy and food.National Outlook Report, CSIRO

The project provides projections for more than 20 scenarios, exploring different potential trends for consumption and working hours; energy and resource efficiency; agricultural productivity; new land-sector markets for energy feedstocks and ecosystem services; national and global abatement efforts, climate, and global economic growth.

While our major focus is on Australia, at the national scale, we also model what might happen globally, and at more detailed state and local scales within Australia.

We find economic growth and environmental impacts can be decoupled − in the right circumstances. National income per person increases by 12-15% per decade from now to 2050, while the value of economic activity almost triples.

In stark contrast to income, which rises across all scenarios, environmental performance varies widely. Key environmental indicators such as greenhouse gas emissions, water stress, and native habitat and biodiversity are projected to more than double, stabilise, or fall across different scenarios to 2050.

As shown in the chart below, we find that energy rises in all scenarios, but that greenhouse emissions can fall at the same time – with the right choices and technologies. Water use can also rise without increasing extractions from already stressed catchments. Food output (here indicated by protein) can increase, while native habitat is restored.

Growth of what?

We use the normal definition of economic growth as measured by increase in Gross Domestic Product (GDP) – the value of goods and services produced in an economy – consistent with the national accounts framework.

Some authors use a different definition, most notably Herman Daly a leading advocate for a steady state economy. Daly defines growth as an increase in physical economic scale, such as resource extraction, and goes on to argue that indefinite (material) economic growth is not possible.

While this may be true, for his definition, it can be confusing for people that do not realise he is not referring to GDP growth. Indeed, Daly recently acknowledged that economic (GDP) growth is possible with finite resources and steady material throughput.

These definitions matter: we project growth (GDP – measured in real dollars, adjusted for inflation) increases by more than 160% in scenarios where domestic material extractions and throughput (measured in tonnes) decreases by around 40%.

Choosing a sustainable future

But here is the real crunch: we find these substantial steps toward sustainability could build on policy approaches that are already in place in Australia or other countries. This implies Australia could make enormous progress towards a more sustainable future without a major change in what we value.

We can be confident that a values shift is not required to achieve these outcomes – at least before 2050 – because none of the scenarios we modelled assume change in values or a new social or environmental ethic.

Instead, we show that people will make choices to change their behaviour to make the best of particular policy settings. These choices shape production and consumption.

For instance, we consider increasing Australia’s climate effort in line with other countries would be consistent with Australian public opinion and assessments of Australia’s national interest in limiting the rise in average global temperature to 2°C. So we do not interpret this as implying a change in values.

But we find collective choices are crucial. For example, individual choices about whether to drive or catch a train to work are strongly shaped by prior collective choices about transport infrastructure. Collective choices are often, but not always implemented through changes in government policy, legislation, and programs.

We find collective choices explain around 50-90% of differences in environmental performance and resource use across the scenarios we model. Consistent with the institutional reform approach, we find top-down collective choices are particularly important in shaping “public good” outcomes – accounting for at least 83% of the difference between scenarios for greenhouse gas emissions.

Bottom-up individual choices play a greater role when private and public benefits are aligned. For instance individual choices account for up to half of the difference between scenarios for energy use (33–47%) and non-agricultural water consumption (16–53%).

While individual choices are important, we find decisions we make as a society are likely to shape Australia’s future sustainability more than the decisions we make as businesses and households.

Sustainable prosperity is possible, but not predestined. Australia is free to choose.

Steve will be on hand for an Author Q&A between 9:30 and 10:30am AEDT on Friday, November 6, 2015. Post your questions in the comments section below.

Concerns about drought and water supply are once more building in eastern Australia. Recent reports from Victoria show the state government is considering switching on the so-far-unused desalination plant to supply Melbourne. While Melbourne doesn’t currently need extra water, this might free up other water allocated to the city to be diverted to regional communities in the north of the state where water shortages are looming.

When drought strikes, people and governments look to shore up water supplies. In Australia, politicians have focused on building more dams and long pipelines, at the expense of alternative sources such as recycled water.

It has been widely assumed that drinking recycled water, from sources such as sewage, is not acceptable to the public. But an Australia-first survey released by the Australian Water Association shows the public is ready to accept recycled water.

Water is getting further away and more expensive

Since colonisation, we have tapped increasingly distant, more energy-intensive and more expensive sources of fresh water.

We have constructed large dams to buffer variable water supplies through wet and dry seasons, as well as wet and dry years. As water consumption has exceeded the capacity of river basins to meet demand, we have constructed long pipelines, to pump water in from less populated river basins to more populated basins.

During the last decade, many of our major cities began to identify that the capacity to pump more water from distant locations was approaching sustainable limits.

New sources of water were required. So, in a very short period of time, cities including Perth, Sydney, Melbourne, Adelaide and the Gold Coast set about constructing seawater desalination plants.

Hindsight comes with 20-20 vision and it’s clear that most of these desalination decisions – with the notable exception of Perth’s – were premature since the plants have barely beeen used. Politicians and those with a financial interest in these plants often comment that the desal plants represent great “insurance policies” for when the next drought inevitably arrives.

However, these “insurance policies” came with billion-dollar price tags. Much of this has been externally financed, thus accruing significant annual interest costs.

Furthermore, the costs associated with maintaining desal plants are significant – even when they supply zero or negligible water. In some cases, such as Sydney, the real need to use the desal plant – given effective demand management – is likely to be still many years away. As such, it is arguable that these desal plants were very poor value insurance policies.

I argued that the technology was established to reliably purify water from sewage treatment plants to such a high degree that it would be capable of providing extremely high-quality drinking water for Sydney. This practice has been adopted in a number of US cities and is commonly referred to as “potable water recycling”.

All towns and cities are physically unique in terms of geography and historic development features. However, in the right mix of circumstances, potable water recycling can have significant advantages over seawater desalination.

These can include reduced operation and construction costs, as well as much lower energy requirements, which translate to reduced carbon emissions. Nonetheless, the suggestion that the NSW government seriously consider potable water recycling as an alternative to seawater desalination was not widely appreciated.

The general wisdom of the time was that Australians would not be prepared to accept water that was once sewage as a component of their drinking water supply. Indeed, this appeared to be supported by a telephone survey around that time.

Since then, the New South Wales and Victorian state governments have made statements that potable water recycling is not even an option for consideration by cities in those states.

Political thirst for dams

It is widely recognised that most opportunities for building dams on rivers to provide water for Australia’s large cities have been effectively exhausted.

Nonetheless, Australian politicians appear to yearn for opportunities to announce a new big dam project. When the federal member for Calare, John Cobb, announced a plan to dam the Belubula River at Needles Gap (NSW) in 2014, he declared: “I believe this project will lift the spirits of the central west and will inspire all of regional Australia.”

Water supply projects may have many diverse objectives, and inspiring all of regional Australia may be an understandably important one for a politician. However, many politicians appear to carry some unshakeable assumptions about community water supply preferences in Australia. Most seem to think we all want to hear announcements for new big dams.

And if we can’t have new big dams, they think desalination plants are our next preferred option. Few politicians deny the sustainability advantages of potable water recycling, but most seem to think it’s just too difficult to bring the community on board to support it.

Attitudes are changing

In the recent survey, 3,316 completed responses were received from community members across Australia.

Of these, 69% agreed or strongly agreed with the statement that recycled water “can be treated and managed for safe drinking”. This compared with 56% who agreed with the same statement for stormwater and 82% who agreed for seawater desalination.

Given the prevalence of actual seawater desalination plants around Australia and a lack of any public discussion about potable water recycling, I suggest that this level of faith in the capabilities of recycling plants is remarkable.

Recent research from the United States has shown that by engaging the community and providing accurate information, the underlying level of support for recycling can be significantly increased.

When consumers were asked whether they agree with the statement that “there is scope for more dams to provide additional water supplies in the south of Australia (e.g. in the Murray-Darling Basin and the south-east coastal areas)”, only 33% agreed. This rose to 46% for northern Australia. So much for inspiring all of regional Australia.

When this happens, we can expect many regional areas to struggle in their management of dwindling water supplies. Many will be searching for sustainable water supply solutions and some will identify potable water recycling as the most sustainable option for their circumstances.

The challenge for the federal and state governments will be to support the needs of these towns and cities. They will do that best by ensuring that all potential water supply options are on the table and given fair consideration.

In the meantime, our politicians would serve regional Australia best by ceasing to stigmatise potable water recycling as an option that is not even entitled to consideration.

Instead, they should work to build upon the support that currently exists in our communities so that when the need arises, potable water recycling is a viable and broadly accepted water supply solution. There is already powerful evidence that this can be achieved, when state governments work constructively toward this goal.

In 2013, the Western Australian government gave strong support and approval for a potable water recycling project to provide up to 20% of Perth’s water supply. That plant has since been constructed and will soon begin replenishing one of the city’s essential, but dwindling, groundwater supplies.